Light waves travel through the process of electromagnetic radiation. The combination of electrical and magnetic fields that light has is what gives light the distinct quality of being able to travel with or without a medium, which is unlike other wave forms.
No one had deduced that light traveled in waves until Thomas Young in 1801. Through his experiment, which filtered a beam of light through a narrow slit in a playing card, Young saw that light left an imprint much like a bar code. He explained this by stating that light moves in waves, with high points and low points, just as a wave traveling in the ocean has peaks and troughs. Scientists were baffled as to how light waves could move through space and time without a medium until the work of James Clerk Maxwell. He was the first to state that light waves produce electromagnetic fields of radiation, which he discovered operate with or without a medium.
Later on, Einstein showed that light was dually a wave and a subatomic particle called a photon. The photon is a unique particle because, as it travels, it carries force but has no mass. It is this duality of light, being both wave and particle, that allows it such a diverse and wide range of abilities and effects on the natural world. This unique combination of elements makes light waves unlike anything else humans have encountered.